refactor: remove redundant save_meta implementation from BinaryMetaPlugin

Co-authored-by: aider (openai/andrew/openrouter/qwen/qwen3-coder) <aider@aider.chat>

src/meta_plugin/system.rs

@@ -82,18 +82,6 @@ impl MetaPlugin for BinaryMetaPlugin {
         Ok(())
     }
     
-    fn save_meta(&mut self, conn: &Connection, item_id: i64, value: String) -> Result<()> {
-        let meta_name = self.meta_name();
-        debug!("Saving metadata: item_id={}, name={}, value={}", item_id, meta_name, value);
-        let meta = crate::db::Meta {
-            id: item_id,
-            name: meta_name,
-            value,
-        };
-        crate::db::store_meta(conn, meta)?;
-        self.saved_during_io = true;
-        Ok(())
-    }
 }
 
 impl CwdMetaPlugin {